Cottees' 1987 Sigma GN GSR Super Edition

[Cottees]

I did open it up when I got it and had a quick look, but it would be worth having a closer look.

This is the insides of a Bosch 9 260 060 023 ECU. The one found in the Manual TR.




Next step is to work out exactly where the water leak is. Then take the head and timing chain cover off and reassemble everything again. I have a feeling I might have damaged the head gasket when I changed over timing chain covers.

[Superscan811]

These are the Electrolytic Capacitors. usually they are 47u 50v

Have a good look around them for any corrosion, usually the copper will go a powdery green and the solder will be a powdery grey colour.

Cheers.

[75wagon]

Just to let you know, I haven't posted on this post (I may have but I don't remember), I read this everytime something there is a new post.
Keep up the good work.
I rate the effort you are putting into this build, and I can't wait till you get this going and get this on a cruise

Dave...

[JJPotter]

Nice work, hope it works out in the end .

Another thing you may want to check the ECU for is dry joints. I couldn't see anything in the pics you supplied (you may need to have a closer look, maybe use a magnifying glass).

I found an page with a picture of a dry joint on Google which is what you should be looking for - http://www.google.com.au/imgres?imgurl= ... CBsQ9QEwBQ - the web site also has a lot more technical info on fault finding electronic PCB's (Printed Circuit Board) if you have a soldering iron and are willing to have a go .

Smoke on the PCB is also a bad sign that something has gone wrong, but as long as it's not an SMD (suface mount component - the leads of the electronic component sit on the surface of the PCB instead of going through it) it shouldn't be too hard to replace (again, I couldn't see anything on the pics supplied, but there may be something on one of the other boards sticking out of the main one ).

[Cottees]

The milkshakes are on me!


I visited the Sigma again and gave it a quick vacuum (forgot to take pics), and to try and work out where the water is leaking. Firstly I took the regular hose off the water pump and replaced it with a longer one, and made it point up. I poured water into the hose and saw that it dropped a bit once it was full. I left it for a couple min and had a listen and could hear a dripping sound from behind the timing chain cover. I filled the hose a couple more times and tried looking down the timing chain cover to see if I could see a leak, but couldn't. Next I blew into the hose and could hear bubbles coming from behind the timing chain cover. This makes me think that it is a seal problem on the timing chain cover, and not the head. I will take the timing chain cover off again, re-seal it, and try pushing water into it again and see if it leaks.

Thanks for all the advice and help everyone. At the moment I think the ECU + electronics might be ok. I think the reason why it was running like crap was because the oil was almost as thin as water. I will open the ECU and have another look over it again though.

[Cottees]

Yesterday I drained the 'oil' out of the car, and more water than oil came out. To take the timing chain cover off, I had to take off the AC bracket, and to take the AC bracket off I have to take off the intake. In the middle of taking the intake off, my back decided to give up, so I am leaving it for a couple days. Since the intake is off at the moment, I decided today to clean it up, and pull apart the throttle body and give that a good clean too.

[Billsy]

that head will be fine, its easy to bugger the gasket on the timing case though.

hope you get it sorted soon, sounds to me like its got some electrical issues, plugs wrong or injectors not firing properly/or in the right order

[Cottees]

that head will be fine, its easy to bugger the gasket on the timing case though.

Yeah, I don't think I sealed the timing chain properly. I suspect that once I get proper weight oil into the engine, and it not be highly watered down, it should run better. I have read that the Astron can run really rough when it has oil that is too thin, and mine was running on mostly water.

[Superscan811]

If the engine is going to sit, even for a short time, you don't want the internals to rust so I would buy 2 oil filters and 10L of cheap oil and:
1. Dump the water, oil and oil filter.
2. Re-fill with cheap oil and run the engine for a minute (without water).
3. Dump the oil and oil filter again.
4. same as 2.

Just a thought.

Cheers.

[Cottees]

I hope to be able to get the engine re-sealed and back together by around Sunday. It would have been sealed and back together today if it wasn't for my injured back. The oil and water are already drained from the car. Once I get it back together, then I can flush out the engine with some oil.

[Cottees]

I now have the timing chain cover sealed up again, and will able to start testing tomorrow.

This is the oil that came out of the engine.


I also cleaned out the throttle body while it was out of the car. I used some CRC Carbie cleaner. Damn that stuff is toxic, but cleaned it up pretty well.

[duanepurcell1]

nice work mate i have read all you have put in to it and wish you all the best and would like to know if by any chance once you have everythin sorted out on ya siggy what would you charge to make a wireing loom to suit my gk im interested in doing this conversion too both my sigmas i only live 5mins away from upull it and would like to catch up for a chat

[Cottees]

nice work mate i have read all you have put in to it and wish you all the best and would like to know if by any chance once you have everythin sorted out on ya siggy what would you charge to make a wireing loom to suit my gk im interested in doing this conversion too both my sigmas i only live 5mins away from upull it and would like to catch up for a chat

It wouldn't be too hard to make some more looms. I would wait till I am 100% sure mine works first.

[Cottees]

Almost got the engine back together. Ran out of time today, but should be able to get the rest done and get it started again.

[duanepurcell1]

no worries mate ill keep an eye on your progress lookin good so far keep up the good work

[Cottees]

I got the engine back together. The oil and water are not mixing. And the car is still running like crap. Looks like more testing to see what is wrong.

http://www.youtube.com/watch?v=8BDPkpIqEsQ

The petrol has been sitting in the tank for 6 months +. Anyone know if that is long enough for petrol to go bad?

[GB_BB4C]

The petrol in my GK sat for 3yrs and started fine. Wasn't much left in the tank though and now has new stuff in it. Send me a PM if ya wanna try another comp as i have a couple just sitting here that i know work.

[Cottees]

I was bored so I had an idea to add bluetooth to a Megasquirt ECU. Did some research and there is some RS232 to Bluetooth adapters, but I didn't want to have to attach something external to the ECU for that functionality. I did some googling and came across this : http://www.sena.com/products/industrial ... d100v2.php . It would be something that could be easily attached internally to a Megasquirt ECU.

[Superscan811]

Or this
Jaycar Serial to bluetooth

or these

Lantronix serial to WiFi

There are lots of stuff that will work well.

Just read you didn't want to attach something external.
Please disregard.

Cheers.

[Cottees]

Please disregard.

If I can find a cheap RS232->BT external adapter, it wouldn't be too hard to pull it apart and integrate it into the ECU.

[Cottees]

Just put 20L of petrol into the GN to see if that will make any difference, but I think the ECU might have just given up. The Diagnostic light flashes to say there is nothing wrong, try and start, and the light just says on. So I am pretty sure the ECU is at fault, but will be able to make sure tomorrow.

[Cottees]

With help from GB_BB4C, the GN is sounding less like a tractor, and more like a car.

While trying a better computer, it returned the codes 13 (Intake Air Temp Sensor), 22 (Crank angle sensor circuit), 31 (Knock Sensor circuit) and 41 (Fuel Injectors). That was when it wouldn't start. I changed to another Intake Air Sensor, and it started. The Knock Sensor error I was expecting since there is no Knock Sensor installed. 22 and 41 could mean I have a stuffed dizzy and injector(s), so I will have to retest them and that part of the loom. There is also an exhaust leak, and a head gasket leak at the front of the engine. I expected the head gasket to leak where it did. I'll just have to get a new head and exhaust gasket.

From what I can see, the problem with my ECU was that one of the capacitors did start to leak. I'll try and repair it before buying another one.



Couple things I forgot to say is that the spark plugs that I was using were pretty dirty, which wouldn't have helped. One of the solder points for the leaking capacitor was also a dry joint.

[Cottees]

Had a close look at the ECU to find out which capacitors I need to get. If I replace them all, then I'd need:
2x 100μF 16v
1x 22μF 50v

The closest I can find is:
Cap Electro RB 100 uF 16 WV (32c)
http://www.dse.com.au/cgi-bin/dse.store ... View/R4360
Cap Electro BIPOL 50V 22 uF (65c)
http://www.dse.com.au/cgi-bin/dse.store ... View/R4640

100uF 16V RB Electrolytic Capacitor - 105oC (40c)
http://jaycar.com.au/productView.asp?ID=RE6130
22uF 50V Bi-Polar RB Electrolytic Capacitor (85c)
http://jaycar.com.au/productView.asp?ID=RY6816



Also have found this site and they have everything I need. I'll also be getting the more expensive ones. They are only a little more, so not too bad, and they *should* give me less problems.

[SE Wagon]

As a minimum, get 25V capacitors! The 16V rating will be at a nominal 20 or 25 deg C. At higher temperatures that rating comes down, and you're not far off your alternator's charge voltage. There's not a lot of margin there when the car gets hot, which is (some argue) why the capacitors fail in the first place.

Go 25V capacitors for the extra margin.

Edit: just saw the ratings - looks like the Jaycar caps are rated much higher than that. I'd still try for 25V caps.

[Cottees]

Oops, forgot to post the URL of another place I found some.

http://au.farnell.com/

The ones I was looking at were rated for up to 105°C - 130°C.

http://au.farnell.com/jsp/search/produc ... ku=8127026
http://au.farnell.com/jsp/search/produc ... ku=8126240

[Superscan811]

Definately replace ALL the electrolytic caps. If one is dead, the others are well on the way.

Cap Electro BIPOL 50V 22 uF (65c)

NO, these are used for filters for a sound system.

Jaycar, Farnell, Wagner Electronics, RS Components are all good sources for components but before you buy, please tell them it's for an automotive product with no cooling.

Get the highest temp rating you can and don't go too high above the rated voltage on the cap.
The rated voltage also affects the capacitance, ie: if a cap is rated at 100u at 100v, at 10v it will probably be around 60u.
Also low ESR caps thend to be better as well.

It's almost always the temp that will kill an electrolytic cap because it's filled with a liquid (the electrolyte) and when it gets too hot, it "boils" the electrolyte, which makes the cap leak.
It will boil because of too higher voltage or the ambient temp is above spec.

End of the electronics lesson for today.

Cheers.

[SE Wagon]

The rated voltage also affects the capacitance, ie: if a cap is rated at 100u at 100v, at 10v it will probably be around 60u.

Do you have a link to this information? AFAIK, capacitance is a combination of physical construction and materials. The voltage rating indicates the maximum voltage the capacitor can withstand before breaking down in some fashion.

I've never worried about voltage rating when using a meter to measure capacitance.

[Cottees]

I think it would just be easier and safer to just use direct replacements, but with the highest temp rating I can get. The caps I am looking at from Farnell are 105C-130C, so it should be ok for automotive use.

[Cottees]

I just received some new caps for my ECU.



I ordered them from Farnell around 16:00 Monday, and they arrived around 11:30 Tuesday. Very fast shipping. I ended up ordering double I needed, just in case. One problem with the caps is the larger caps on the board, the replacement I got was smaller. They are the same rating and 105C, so they should work the same.

[DanTurboLancer]

How is it all coming along mate?

Geez you must have some patience,
I would have gone and got another computer months ago